de Access Firefox Project (desarrollador) el Mayo 25, 2015 · enlace permanente

I've tested the version (0.0.8) that's available on this site in the latest Thunderbird (31.7.0) and it is installing and functioning as it should. I installed it through the Add-ons Manager (after searching for Zoom), and by manually installing it and experienced no problems or issues.
This version was also tested in Earlybird and Daily (41.0a1) and it worked in those too.
I'm also a user myself.

Please provide detailed information on the issue(s) that you have.
Thanks.